Unmanned Systems Technology 006 | ECA Inspector Mk2 USV | Antenna systems | Northwest UAV NW-44 | Unmanned ground vehicles | Navigation systems | Lunar X challenge

ECA Inspector Mk2 USV | Dossier an aircraft’s fly-by-wire controls would. In direct remote control steering mode, the operator uses the normal interface but the software intervenes to provide a smooth, predictable and intuitive response. Regardless of whether the USV is operating in an autonomous or assisted mode, underwater imaging sensors such as side-scan sonars and multi-beam echo-sounders demand very accurate steering to preserve their data quality. The Inspector Mk2 however stays within 5 m of the planned track thanks to the hull and propulsion system design in combination with the steering software. A compromise has to be made though 29 “Maybe at the top of sea state 4 it is difficult to be sure [which of] the 100 echoes, say, is the real obstacle,” Clavier explains. Fusing data from sensors including radar, infrared cameras and other sensors has enabled the company to produce good obstacle and target detection capabilities, but further improving it remains a major focus of ongoing development work, he says. As an alternative to supervising autonomous operation or managing the mission with high-level commands, the operator can also steer the Inspector Mk2 directly, but even here the computer system provides assistance in the way between the highest accuracy of position and stability of the sensor. If the system is constantly making small, rapid corrections for the sake of path accuracy it destabilises the sensor and degrades the imagery. For this reason, Clavier explains, development of the steering commands was a slow process that started with the USV programme in 2008. “We didn’t have the correct commands at the beginning, but it was perfectible and now I think we are very accurate. I think we have the best compromise,” he says. Customer requests for a version of the craft able to tow minesweeping gear provided an opportunity to refine the command set further. Developing commands suitable for a towed system alongside those optimised for hull- mounted sensors enhanced their ability to ensure that they could steer a USV on a sufficiently accurate track while maintaining the stability that the sensors demanded. “At the beginning that wasn’t the case; the first USV was not at the stability level that this one is,” Clavier says. As the Inspector Mk2 is an optionally manned vessel, it has a full set of controls in its six-seat cabin, and the control system enables the driver to use all of the autonomous guidance and assisted steering modes in addition to direct steering. It also allows the crew to use all the mission system’s functionality. The boat can be considered a means of putting a set of sensors and effectors into the right place at the right time to collect information and act on it, or get it to others who can act on it. ECA offers a number of mission-focused suites that have many items in common, mixed and matched to produce different emphases for different but related missions. None of the combinations are set in stone though, as all of them can be tailored to a customer’s needs. For example, in missions that primarily involve surface surveillance and/or protection tasks, the bow keel arm is most likely to be in its above-deck position and fitted with a searchlight rather than a sonar. For missions requiring interdiction Unmanned Systems Technology | February/March 2016 Artist’s impression of the extended variant of Inspector Mk2 in fire-fighting mode for tackling blazes on offshore platforms Heeling into a turn at speed in choppy water against the background of the French Navy’s Mediterranean base at Toulon